1. Field of the Invention
This invention relates generally to laryngoscopes and more particularly to a laryngoscope blade which provides an increased viewing area.
2. Prior Art
A laryngoscope is an instrument employed for examining the larynx and also serves as an aid for inserting an endotracheal tube through the larnyx into the trachea. Present laryngoscopes employ a blade having a relatively small light source mounted near its tip. The blade has upper and lower walls for maintaining the patients gums spread apart and for depressing the tongue. A tip portion of the lower wall is employed for lifting the epiglottis and the larynx is examined by sighting between the upper and lower walls. When the epiglottis is lifted by the tip portion of the blade, an endotracheal tube can be inserted into the trachea. Usually, the trachea is depressed externally by the physician's fingers so that it is more closely aligned with the patient's mouth, thereby providing a larger viewing area within the larynx.
Examination of the larynx of patients under the age of about 6 months presents a problem not found in older patients. That is, such infant patients have a relatively short neck, inhibiting sufficient head movement to permit the physician to observe a sufficient portion of the larynx. More particularly, the restricted head movement of an infant does not permit as much alignment of the mouth with the trachea as can be obtained in older patients. Presently available laryngoscopes have a relatively narrow field of view. Accordingly, the use of presently available laryngoscope blades for the examination of the larynx of infants does not permit the physician to observe a sufficient amount of the larynx.
When an endotracheal tube is being inserted into the trachea by the physician, the physician's one hand must hold and manipulate the laryngoscope while the other hand is holding and inserting the endotracheal tube. As mentioned above, it is often necessary for the physician to externally depress the trachea to more closely align it with the mouth opening while inserting such an endotracheal tube. In order to perfrom all of these functions, the physician must employ some fingers of the hand holding the laryngoscope to externally depress the trachea. However, presently available laryngoscope blades are either too short, such that they cannot be employed for reaching the epiglottis of all patients, or are too long, such that the dual functions mentioned above cannot be performed by the same hand.